See also: Zephyr

Zephyr is a protocol of Instant messaging and a succession of applications functioning under Unix, conceived with the Massachusetts Institute off Technology (MIT) like part of the Athena project. According to philosophy “Made a thing, make well it”, of Unix, this continuation is made up of several separate programs functioning together to carry out a complete mail system.

Still used today in some universities like the Carnegie Mellon University, the University of Stanford, and of course the MIT, Zephyr was largely replaced by modern and more popular mail systems instantaneous like AIM and Jabber.

The software Pidgin makes it possible to use the Zephyr protocol (among much of others).

Zephyr uses datagrams UDP transmitted between ports 2102,2103 and 2104. It is incompatible with the majority of the routers who make translation of addresses (NAT) because it transmits internal IP address, and that the datagrams " réponse" are thus not correctly roads with the return. It only uses the authentification by Kerberos 4, and nobody invested the required effort to convert it with Kerberos 5.